Comment 3 for bug 985389

One obvious way to fix the first issue would be:

=== modified file 'softwarecenter/ui/gtk3/panes/softwarepane.py'
--- softwarecenter/ui/gtk3/panes/softwarepane.py 2012-04-12 12:10:50 +0000
+++ softwarecenter/ui/gtk3/panes/softwarepane.py 2012-04-23 13:49:37 +0000
@@ -123,7 +123,7 @@
         self.search_term = ""
         self.application = None
         self.limit = 0
- #~ self.filter = None
+ self.filter = None
         self.vadjustment = 0.0

But there is a regression risk here as the filter is also used for global fitlering like showing "supported" only. So we probably
need to selectively reset the filter.